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Chase-devil, common St. John's-wort, Klamath weed, millepertuis commun, Tipton's weed

brushy mountain St. Johnswort

Habit Herbs perennial, erect or ± spreading, branching at base and beyond, (3–)4–7(–7.8) dm.
Stems

internodes 4-lined.

Leaves

ascending to widely spreading, sessile;

blade narrowly lanceolate (linear-lanceolate on axillary branches), 10–40(–55) × 5–10(–13) mm, longer than internodes, leathery, margins plane, apex acute to acuminate, densely gland-dotted, basal vein 1, midrib with inconspicuous branches.

Inflorescences

cylindric, to 40-flowered; branching mostly dichasial, subsidiary branches usually with relatively smaller leaves.

Flowers

8–15+ mm diam.;

sepals lanceolate, unequal (outer slightly wider than inner), 3–6(–7.5) × 1.1–1.8(–2.2) mm, margins sometimes ciliate, not setulose-ciliate, apex acute or acuminate;

petals orange-yellow, obovate, 5–10 mm;

stamens 50–80, filaments basally connate;

styles 2–4 mm;

stigmas capitate.

Capsules

ovoid, 5 × 3–4 mm.

Seeds

0.4–0.8 mm;

testa linear-pitted.

2n

= 24.

Hypericum perforatum

Hypericum radfordiorum

Phenology Flowering late spring–fall (May–)Jun–Sep(–Oct).
Habitat Granitic outcrops
Elevation 500–800 m (1600–2600 ft)
Distribution
from FNA
AR; CA; CO; CT; DC; DE; IA; ID; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; VA; VT; WA; WI; WV; WY; BC; MB; NB; NF; NS; ON; PE; QC; Europe; Asia (sw Arabia, China, India, Mongolia, Siberia); n Africa [Also introduced widely elsewhere]
[WildflowerSearch map]
[BONAP county map]
from FNA
NC
[BONAP county map]
Discussion

Subspecies 4 (1 in the flora).

Hypericum perforatum has been introduced into various parts of the world, including North America, where only subsp. perforatum is represented. The range of variation in the flora area is less than occurs in Europe, and signs of hybridization that are common there are absent in North America.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 6, p. 99. FNA vol. 6, p. 90.
Parent taxa Hypericaceae > Hypericum > sect. Hypericum Hypericaceae > Hypericum > sect. Brathys
Sibling taxa
H. adpressum, H. anagalloides, H. apocynifolium, H. ascyron, H. boreale, H. brachyphyllum, H. buckleyi, H. canadense, H. canariense, H. chapmanii, H. cistifolium, H. concinnum, H. crux-andreae, H. cumulicola, H. densiflorum, H. denticulatum, H. dolabriforme, H. drummondii, H. edisonianum, H. ellipticum, H. erythreae, H. fasciculatum, H. frondosum, H. galioides, H. gentianoides, H. graveolens, H. gymnanthum, H. harperi, H. hypericoides, H. kalmianum, H. lissophloeus, H. lloydii, H. lobocarpum, H. maculatum, H. majus, H. microsepalum, H. mutilum, H. myrtifolium, H. nitidum, H. nudiflorum, H. paucifolium, H. prolificum, H. pseudomaculatum, H. punctatum, H. radfordiorum, H. scouleri, H. setosum, H. sphaerocarpum, H. suffruticosum, H. tenuifolium, H. tetrapetalum, H. virgatum, H. ×mitchellianum
H. adpressum, H. anagalloides, H. apocynifolium, H. ascyron, H. boreale, H. brachyphyllum, H. buckleyi, H. canadense, H. canariense, H. chapmanii, H. cistifolium, H. concinnum, H. crux-andreae, H. cumulicola, H. densiflorum, H. denticulatum, H. dolabriforme, H. drummondii, H. edisonianum, H. ellipticum, H. erythreae, H. fasciculatum, H. frondosum, H. galioides, H. gentianoides, H. graveolens, H. gymnanthum, H. harperi, H. hypericoides, H. kalmianum, H. lissophloeus, H. lloydii, H. lobocarpum, H. maculatum, H. majus, H. microsepalum, H. mutilum, H. myrtifolium, H. nitidum, H. nudiflorum, H. paucifolium, H. perforatum, H. prolificum, H. pseudomaculatum, H. punctatum, H. scouleri, H. setosum, H. sphaerocarpum, H. suffruticosum, H. tenuifolium, H. tetrapetalum, H. virgatum, H. ×mitchellianum
Subordinate taxa
H. perforatum subsp. perforatum
Name authority Linnaeus: Sp. Pl. 2: 785. (1753) Weakley ex J. R. Allison: Castanea 76: 110, fig. 3. (2011)
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